20 November 2018

Environment

World's water could become scarce if the Amazon rainforest is destroyed

The Amazon rainforest is home to 10% of the world’s species, generates 20% of global oxygen, and creates half of its own rain through an intricate water cycle dynamic.

It’s a natural system that’s a world unto itself — and it faces potentially catastrophic levels of deforestation under the new administration of Brazil’s president-elect Jair Bolsonaro, who has vowed to allow industrial interests to have more access to the forest.

If that happens, the effects would be felt far beyond Brazil. In particular, countries around the world could face droughts and water shortages, according to National Geographic.

That’s because the Amazon influences global rain patterns and is itself a major source of water. The push and pull of the water cycle throughout the 2.125 million square mile forest creates a “giant flowing river in the sky,” Nat Geo reports, which eventually feeds rivers and lakes around the world.

The Amazon is also a major carbon sink and its ongoing absorption of greenhouse gas emissions helps to mitigate global warming and climate change. As temperatures rise, precipitation patterns get skewed — some countries receive more rainfall, while other get less. This is already playing out in the world as many countries face increasingly dry conditions, which undermines agricultural systems and leads to water shortages.

These effects are expected to be felt as far as away as Africa and North America, Nat Geo reports.

If the Amazon continues to decline, it could enter a dangerous feedback loop, where chainsawed trees release greenhouse gas emissions causing temperatures to rise and the forest to dry, weakening the water cycle, and causing further drying.

Earlier in the year, a study showed that the Amazon is very close to reaching this point and could even resemble a desert within the next few decades.

The world is already facing a severe water crisis. More than 30% of the global population is unable to access clean drinking water and the UN estimates that more than 5 billion people could be affected by water shortages by 2050.

A large part of this problem is due to mismanaged natural resources.

In Latin America, Africa, and Asia, for example, most rivers are compromised by pollution from industrial runoff, the UN reports. Further, 80% of global wastewater and sewage is discharged directly into bodies of water, rendering it unsafe. Around two-thirds of forests and wetlands, which are essential to cleaning and maintaining water supplies, have been lost or degraded.

The continual damming of rivers throughout the world, which is common in Brazil, also disrupts water systems.

In various countries, water has become scarce.

For example, Lake Chad has shrunk by 95% in recent decades, putting millions of people at risk of famine. In Shanghai, 85% of the city’s drinking rivers are too polluted to draw water from. Melting glaciers throughout Asia, meanwhile, could deprive millions of people of drinking water.

Earlier this year, Cape Town narrowly averted becoming the first major city in the world to run out of water.

Emerging water insecurity could eventually lead to conflicts. Some analysts argue that the civil war in Syria was partially fueled by a devastating drought linked to climate change.

The good news is that these consequences are not inevitable. If forests like the Amazon are protected rather then cut down, rivers are cleaned rather than polluted, and greenhouse gas emissions are curbed rather than released, then water sources could remain robust well into the future.